State Sen. Carla Nelson, R-Rochester, announced Monday she's running for Democratic Rep. Tim Walz's open U.S. House seat.

Nelson joins Blue Earth Republican Jim Hagedorn in the race. Hagedorn narrowly lost his bid to unseat Walz in 2016.

In recent years, Minnesota's First Congressional district has become increasingly competitive, with Republican and Democratic interests in Washington putting money behind races there.

Nelson had planned a major announcement in Rochester, but truncated her prepared remarks in light of the mass shooting at a concert in Las Vegas.

In a statement, she said that "today is not a day for campaigning."

"I look forward to the days and weeks to come as my campaign gears up, but for now I hope everyone will continue to keep the victims, their families, and the first responders in their thoughts and prayers," she said.

Nelson was first elected to the Minnesota Senate in 2010. Prior to that, she served one term in the House.

Walz is running for governor, and eight Democrats have already announced that they will run for his seat.